Overview
ISO/IEC 13817-1:1996 specifies the base language of VDM-SL (Vienna Development Method - Specification Language). Published by ISO/IEC in 1996, this standard defines a model‑based formal specification language used to describe software systems precisely. The document provides the mathematical representation, abstract and concrete syntaxes, and both the static and dynamic semantics of VDM‑SL, and includes rules for conformity of specifications and supporting tools.
Keywords: ISO/IEC 13817-1:1996, VDM-SL, Vienna Development Method, formal specification, specification language, dynamic semantics.
Key Topics
- Language Scope: Part 1 - Base language of VDM‑SL; foundational constructs for specifications.
- Mathematical Notation: Basic set theory, logic notation, sequences, mappings, ordinals and cardinality used as the semantic basis.
- Core Abstract Syntax: Document structure, type/state/value/function/operation definitions, expressions and statements.
- Expressions & Statements: Local bindings, conditional/unary/binary expressions, quantified and lambda expressions; block, assignment, loop, call/return and exception handling statements.
- Dynamic Semantics: Semantic domains, domain universe (complete partial orders, fixed‑point theory), evaluation functions and verification predicates for types, values, functions and operations.
- Concrete Syntaxes:
- Mathematical Concrete Syntax - notation suitable for human reading and specification.
- Interchange Concrete Syntax - lexical rules and symbol sets for tool exchange and interoperability.
- Auxiliary Material: Patterns and bindings, operator precedence, lexical specification, and a variety of helper functions/predicates for tool implementation.
- Conformity Requirements: Criteria for tool conformance and correct interpretation of VDM‑SL specifications.
Applications
- Formal specification of software: Precisely define system behavior, invariants and interfaces for rigorous analysis.
- Model-based design & verification: Use VDM‑SL models as the basis for verification, refinement and proof obligations.
- Tool development and interoperability: Implement parsers, analyzers and model checkers that conform to the interchange syntax and semantics.
- Safety‑critical and high‑assurance systems: Provide an auditable formal specification language for domains such as aerospace, medical devices and rail signalling.
Keywords: formal methods, model-based specification, safety-critical systems, tool interoperability.
Who Should Use It
- Formal methods engineers, systems and software architects, verification engineers, language/tool developers, and researchers in programming languages and software correctness.
Related Standards
- Other parts of ISO/IEC 13817 (if available) and standards on formal specification languages and tool conformance may complement this base language standard.
This standard is essential when adopting VDM-SL for precise, model‑based system specification, tool support, and formal verification workflows.